Electrolytic apparatus



(No Model.)

I. L. ROBERTS.

ELEGTROLYTI APPARATUS.

No. 442,334. Patented Deo. 9,1890.

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NITED STATES PATENT OFFICE.

ISAIAIIY Il. ROBERTS, OF BROOKLYN, ASSIGNOR OF ONE-HALF TO THOMAS II. MCGRAV, OF POUGI-IKEEPSIE, NICV YORK.

ELECTROLYTIC APPARATUS.

SPECIFICATION forming part of Letters Patent No. 442,834, dated December 9, 1890.

Application filed August 1l, 1890. Serial No. 361,626. (No model.)

To all whom t may concern:

Be it known that I, ISAIAH Il. ROBERTS, a

.citizen ofthe United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Electrolytic Apparatus, of which the following' is a specification, reference being had to the drawings accompanying and forming a part of the same.

This invention pertains to that class of apparat-us designed for the decomposition or purification of solutions of metallic salts, invented by me and characterized by the presence of a diaphragm or partition between the two electrodes, which is substantially non-por- Y ous in the sense that it does not permit the inechanical transfusion of the fluids or solutions under treatment, but which is electrolytic in character in the sense that it permits electrolysis to take place freely through it.

The object of the present invention is `mainly to produce an apparatus of this character designed for such uses as the manufacture of caustic alkali by the decomposition of brine or a solution of common salt.

The improvements which I have devised and embodied in an apparatus of this kind will be described in detail by reference to they accompanying drawings.

Figure l is avcrtcal central section of the complete apparatus for carrying out the in vention. Fig. 2 is a horizontal section of the same. u

I employ as a tank or receptacle for containing the solution to be treated a cast-iron vessel A, of the desired capacity, provided with a cover lll, fitting air-tight. In said cover is a neck or contracted opening surrounded by a rim or flange D. There may be more than one of these openings, provided the tank be of sufficient dimensions to render it necessary.

To introduce the brine into the receiver A, I employ an inlet II, provided with a valve or cock, and an outlet L is used to draw olf the caustic alkali after the process of decomposition has been carried on for a proper length of time.

I utilize the iron receiver Aas the cathode, and connect it by means of a wire K directly to the source of current.

Thean ode proper which I employ isapressed or molded cylinder B, made in substantially the following manner: A quant-ity of carbon, preferably in the form of com min uted or finelydivided retort-carbon, is mixed with a snitable quantity of a substance-such as ozocerite-and heated until the same is thoroughly fused. The mixture is then molded into the desired shapes, highly compressed, and then allowed to harden and cool. This method of making the electrodes I have described in my application filed February il, 1890, Serial No. 34th-IIS.

To the upper rim or edge of the neck D, I secure in any proper manner, as by means of a ring or hoop N, a bag O, which when the cover M is in place reaches nearly to the bottom of the tank A. This bag may be made of some textile material, preferably of cotton strengthened by asbestus cloth, wire-gauze, or any such material that will not be attacked by the solution or the electrolytic products. The anode B is passed down into this bag, and the space around it up to a point slightly above the normal level of the solution in the tank A is filled in with anthracite coal reduced to as finely a powdered condition as possible and packed in around the anode. The anthracite coal is to be ground in such manner as to reduce it to the condition of a practically amorphous or im palpable powder. In this condition, when packed in around the anode, it forms a practically perfect barrier to the mechanical transfusion of Huid. In other words, no solution or liquid of anykind under normal conditions will strain or ooze through it, even by the action of osmose, and in this sense I call it non-porous, as distinguished from those substances heretefore employed as diaphragms, which are in whole or in part distinctly porous and permit the passage or transf nsion of iiuids through them. The mass of coal dust or powder, however, while it is itself practically a non-conductor of electricity, interferes to no perceptible extentwith electrolytic action and the transference of the acid radical to the anode, Since it is moistened throughout with the solution in the vat. I have found, however, that under the action of the current a certain IOO quantity of wateris' carried through the mass of coal-dust and accumulates in the anodeoompartment, rising above the level of the solution in the outcr or anode compartment. To avoid the very objectionable consequences of this peculiar action or property of the current of forcing or carrying along with it the water through the otherwise normally impermeable barrier of coal-dust, I pack into the bag O, for a short space above the coal-dust C and within the neck D, a quantity of grains of plumbago, retort-carbon, or the like. Into this mass extends a pipe F, which serves the twofold purpose of a passage for the escape of the gas generated by the electrolytic -a-c tion and also as an overow to carry off vthe water which may appear in the anode-compartment from the cause above explained. This pipe or passage, being slightly above the level of the solution in the tank, insures the complete saturation of the coalld-ust, but prevents the rise of the Water to an undesirable or injurious extent. The neck above the layer of granulated carbon is `filled with fa lut-ing vof proper material-such `as asphalt or tar-to render the tank air-tight.

Imayem ploy in place of the coal-d ust other materials, such as a paste made of flour and brine or many other substances which I have elsewhere-described as adapted for use in what I term my noli-porous diaphragm; but .I have found that anthracite coal reduced to an impalpable powder possesses peculiar advantages When/used in this apparatus, for-,at

though the coal-'dustitself is practically a nonconductor, the moisture which its-contains permits a free electrolytic action to take place through it,while itis not affect-'ed by an ychem'ical actionand remains Wit-hout change for an indefinite period. I have also found that in the manufacture of caustic alkali by this apparatus the anode exhibits a tendency Ato ldisintegrate under the action of the current, lbut that ythe consequences of such disintegration are entirely avoided by the presence ofv the coal-dust packed around it.

This apparatus may be used for decomposing a great many successive chargesof brine. The action, as I have observed it, is to transfer the acid radical vthrough the packing of coal-dust to the anode, Where it is given off as chlorine gas.- This gas, rising or accumulating i-n the stratum of granulated carbon G, is conveyed off by the pipe F. The solution of caustic alkali left in the tank A is drawn off when of sufficient strength and replaced by a fresh cha-rge. A binding-post P may be embedded in the upper end of the anode, which projects up through the seal or l-uting E.

vembedded in powdered anthracite coal contained in a receptacle in the tank or vat, as set forth.

3. The combination, with an iron receiver constitutinga cathode, of an anode contained in a receptacle Within said receiver and surrounded by a substantially non-porous or 1mpcrmeable mass of -coal-dust, as set forth.

4. In a sealed tank or vat for electrolytic decomposition, an anode-compartment divided off from the cathode-chamber by a non-porous relcctrolytic partiti-on, as described, and provided with an Aoutlet for gas and an overiiow for fluids, as set forth.

5. The combination, with aclosed cathodecompartment, of a closed anode space or compartment, a gas-discharge, and an overovvpipe vfor Water leading 'from the anode-com` partment andv above the level of the solution in the cathode-chamber, as set forth.

6. The combination, VWith the closed iron vessel or receiver constituting the cathode, of the bag Aor receptacle extending into the same, lthe carbon anode contained in said bag, and the filling of coal-dust surrounding'the anode, as described.

7. The combination., with the iron tank or receiver and the cover having a flanged fopening or neck, of the 'bag or receptacle secured in the neck, the carbon anod-e, and the filling of coal -dust surrounding lthe same and contained in the bag.

8. YThe combination, in a closed tank or vat.,

of an anode surrounded 'by a sufbstance such as coal-dust, a gas chamber or space above the same filled with granulated carbon, and a pi pe leading therefrom for conveyingoff the gas, as set forth.

ISAIAH L. RO l--ERTS.

Witnesses: i I

RoBT. F. GAYLORD, PARKER W. PAGE. 

